Fix minor typo in Dockerfiles

Change-Id: Icdbf765e43557d4c2d469998cbf27f43487c76a8
Signed-off-by: garciadeblas <gerardo.garciadeblas@telefonica.com>
diff --git a/docker/RO/Dockerfile b/docker/RO/Dockerfile
index 57c5f6a..b056c3d 100644
--- a/docker/RO/Dockerfile
+++ b/docker/RO/Dockerfile
@@ -33,7 +33,7 @@
     && rm -rf /var/lib/apt/lists/*
 
 #######################################################################################
-# End of common prepration
+# End of common preparation
 
 RUN DEBIAN_FRONTEND=noninteractive apt-get --yes update && \
     DEBIAN_FRONTEND=noninteractive apt-get --yes install \
@@ -106,7 +106,7 @@
 COPY --from=INSTALL /usr/local/lib/python3.10/dist-packages  /usr/local/lib/python3.10/dist-packages
 
 #######################################################################################
-# End of common prepration
+# End of common preparation
 
 RUN rm -f /etc/apt/apt.conf.d/proxy.conf